Prosthetic apparatus with elastomeric shock absorber element

ABSTRACT

Prosthetic apparatus includes a pyramid adaptor and a pylon connected together by an outer sleeve, which may be an elastomeric element. The sleeve or element is clamped to both the pyramid adaptor and to the pylon to provide shock absorbing characteristics and to allow relative axial rotation between the pyramid adaptor and the pylon. Different configurations or embodiments of sleeves are illustrated, and the use of a third clamp is also illustrated.

CROSS REFERENCE TO RELATED APPLICATION

[0001] This application is a continuation-in-part application of Ser.No. 09/828,671, filed Apr. 9, 2001.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] This invention relates to a prosthetic apparatus, and, moreparticularly, to a shock absorber apparatus for a prosthetic leg forboth axial shock absorption and relative torsional or rotationalmovement.

[0004] 2. Description of the Prior Art

[0005] There are generally two problems with prosthetic leg apparatusincluding the inability to absorb shocks and the inability to rotate.Shock absorption increases the natural feel and comfort of the leg, andthe rotation of varying degrees allows a more ordinary turn whilewalking, or allows a combination of pivoting action required for sportsactivities of different types.

[0006] An effort to overcome the problems is shown in U.S. Pat. No.5,800,562, dated Sep. 1, 1998, the inventor of which is co-inventorherein. The '562 patent utilizes elastomeric elements and a springelement to provide both vertical and torsional movement. The elastomericelements provide vertical shock absorber action and, with the springelement, also allow a degree of rotational movement and shock absorberaction.

[0007] Another example of the prior art is found in co-pendingapplication, Ser. No. 09/389,735, filed Sep. 7, 1999, the inventor ofwhich is co-inventor herein. The '562 patent may be considered as thefirst generation apparatus, while the '735 application may be consideredthe second generation apparatus, with the present invention as the thirdgeneration, each of which utilizes an elastomeric element for shockabsorbing capabilities and, with other elements, for torsion relativerotation or movement as well. However, the present apparatus utilizes anelastomeric element for both shock absorbency and torsional resistanceor movement, without the need for other elements.

SUMMARY OF THE INVENTION

[0008] The invention described and claimed herein comprises a shockabsorber for a prosthetic leg utilizing an elastomeric element whichalso offers torsional resistance to allow the user of the prostheticapparatus to rotate, thus simulating the natural movement of a leg andankle. The elastomeric element is secured between a lower pylon elementand an upper pyramid adaptor element and is disposed on the outside ofboth elements. The elastomeric element is the only fixed connectionbetween the pylon and the pyramid adaptor. The extent of the cushioningor shock absorbency and the extent of the torsional resistance may bevaried by different types of elastomeric elements and by the location onthe pylon on which the elastomeric element is secured.

[0009] Among the objects of the present invention are the following:

[0010] To provide new and useful shock absorber apparatus for aprosthetic leg;

[0011] To provide new and useful prosthetic leg apparatus having bothlongitudinal or axial shock absorber characteristics and rotationalpivoting characteristics;

[0012] To provide an elastomeric element disposed outside of a pylon andsecured to a pylon and a pyramid adaptor;

[0013] To provide an elastomeric element having a plurality ofvertically extending grooves disposed outside of a pylon and secured toa pylon and a pyramid adapter;

[0014] To provide new and useful prosthetic apparatus for absorbingaxial shocks and for permitting twisting or torsional relative movement;

[0015] To provide new and useful prosthetic apparatus including apyramid adaptor and a pylon secured together by an elastomeric element;and

[0016] To provide new and useful elastomeric elements usable in aprosthetic apparatus and having different torsional and longitudinalshock absorbing characteristics.

BRIEF DESCRIPTION OF THE DRAWING

[0017]FIG. 1 is a perspective view of the apparatus of the presentinvention.

[0018]FIG. 2 is an exploded perspective view of the apparatus of FIG. 1.

[0019]FIG. 3 is a view in partial section of the apparatus of FIG. 1.

[0020]FIGS. 4, 5, and 6 are perspective views of alternate embodimentsof a portion of the apparatus of FIGS. 1, 2, and 3.

[0021]FIG. 7 is a perspective view of another alternate embodiment,partially cut away, of a portion of the apparatus of FIGS. 1, 2, and 3.

[0022]FIG. 8 is a front view of another alternate embodiment of thepresent invention.

[0023]FIG. 9 is a top view of the apparatus of FIG. 8, taken generallyalong line 9-9 of FIG. 8.

DESCRIPTION OF THE PREFERRED EMBODIMENT

[0024]FIG. 1 is a perspective view of prosthetic shock absorberapparatus 10 of the present invention. FIG. 2 is an exploded perspectiveview of the shock absorber apparatus 10 of FIG. 1. FIG. 3 is a view inpartial section of the shock absorber apparatus 10. For the followingdiscussion, reference will be made to FIGS. 1, 2, and 3.

[0025] The prosthetic shock absorber apparatus 10 includes a pyramidadaptor 12 movable relative to a pylon 30. The pyramid adaptor 12includes an upper portion 14 and four spaced apart screw bores 16, wellknown and understood in the industry. The screw bores 16 are disposed atthe top or upper portion 14 of the pyramid adaptor 12. Extendingdownwardly from the upper portion 14 is a generally circular clamp land18. Below the clamp land 18 is a lower cylindrical portion 20. Thecylindrical portion 20 is relatively long, as compared to the upperportion 14 where the screw bores 16 and the clamp land 18 are located.

[0026] The cylindrical portion 20 has a diameter which is slightly lessthan the diameter of the clamp land 18. The outer diameter of the lowercylindrical portion 20 is less than the outer diameter of the clamp land18, and the outer diameter of the clamp land 18 is less than thediameter of the upper portion 14 of the pyramid adaptor 12 where thescrew bores 116 are disposed.

[0027] The cylindrical portion 20 of the pyramid adaptor 12 extends intoa bore 32 of the pylon 30. Relative movement between the pylon 30 andthe cylindrical portion 20 is enhanced by a bushing 34. The bushing 34is disposed on the inner bore portion 32 of the pylon 30. The pylon 30is a tubular cylindrical member, and the lower cylindrical portion 20extends into the bushing 34 in the bore 32 of the pylon 30. The bushing32 is appropriately secured to the upper portion of the pylon 30, with atop 36 of the bushing 34 disposed on the top of the pylon 30.

[0028] The cylindrical portion 20 moves in the bushing 34 and in thebore 32 of the pylon in accordance with the movement of the user of theprosthetic apparatus 10. The relative movement between the two elements12 and 30 is limited both axially and rotationally by an elastomericsleeve or element 40, as discussed below.

[0029] While the length of the bushing 34 is shown in FIG. 3 ascoinciding with the length of the cylindrical portion 18, this is merelyillustrative. As will be understood, relative movement between thecylindrical portion 18 and the pylon 30 would, of necessity, render adifferent visual effect from that illustrated in FIG. 3.

[0030] Disposed on the outside of both the pylon 30 and the pyramidadaptor 12 is the elastomeric element 40. The elastomeric element 40provides the shock absorbing characteristics and also allows a twistingor torsional relative movement between the pyramid adaptor 12 and thepylon 30. As is well known and understood, the pylon 30 extends to aprosthetic foot appliance. Such prosthetic foot appliance is, of course,not illustrated in the present drawing.

[0031] The elastomeric element 40 is secured to the clamp land 18 of thepyramid adaptor 12 by an appropriate upper clamp 50. The elastomericelement 40 is secured to the pylon 30 by a lower clamp 52. Thus, theelastomeric element is the only element connecting the pyramid adaptor12 and the pylon 30.

[0032] The extent to which the elastomeric element 40 absorbs shocks andpermits twisting or torsional relative movements depends on severalfactors, including a stiffness or resilience of the element 40 and theinherent characteristics of the element 40, which may be variedaccording to the thickness of the elastomeric element, the compositionof the elastomeric element, and various design factors of theelastomeric element, as will be discussed below in conjunction withFIGS. 4, 5, 6, and 7.

[0033] In addition to the design or characteristics of the elastomericelement 40 itself, a third clamp may be used to also vary both the shockabsorbing characteristics and the torsional characteristics of theelastomeric element 40 by the location of such third clamp relative tothe pylon 30. This is illustrated by an intermediate clamp 60, and itsplacement. The clamp 60 is illustrated in FIGS. 1, 2, and 3. The higherthe clamp 60 is located on the pylon 30, or the closer to the upperportion of the pylon 30, the less the shock absorbing characteristics ofa given elastomeric element, and the more limited the torsionalcapability of the elastomeric element will be. Obviously, such thirdclamp may or may not be advantageous, depending on the variouscharacteristics as discussed above, and this will be discussed in detailbelow, of a given elastomeric element.

[0034] Various configurations of elastomeric elements are illustrated inFIGS. 4, 5, 6, and 7, which comprise perspective views of elastomericelements. In FIG. 4, an elastomeric element 70 is shown. The element 70includes a smooth upper portion 72 and a smooth lower portion 74. Thesmooth portion 72 and 74 are, respectively, the upper portion and lowerportion which receive clamps for clamping the element 70 to,respectively, the pyramid adaptor 12 and the pylon 30.

[0035] Between the smooth portion 72 and 74 is an intermediate portion76 which comprises a plurality of circular ribs 76. The relative lengthof height of the ribs, and the extent of their thickness and therelative thickness of the element between the ribs, or the indentationsbetween adjacent ribs, will vary the characteristics, for both the shockabsorbing characteristics and the torsional characteristics of theelement 70.

[0036] A different type of shock absorber element is shown in FIG. 5, inwhich a shock absorber element 80 is shown in perspective. The shockabsorber element 80 includes a smooth upper portion 82 and a smoothlower portion 84. The portions 82 and 84 are, of course, the clampinglocations for securing the element 80 to the pyramid adaptor 12 and tothe pylon 30. Between the two smooth portions 82 and 84 is anintermediate portion 86 through which extends a plurality oftriangularly configured apertures. The triangular apertures are shown inalternate “up” and “down” arrangements. The use of such apertures is, ofcourse, to vary the shock absorber and rotational characteristics of theelement 80. The size of the apertures may vary, and the spacing betweenapertures and between rows of apertures, may also vary, depending on thecharacteristics desired of the element.

[0037]FIG. 6 is a perspective view of another shock absorber element 90.The element 90, like the elements 70 and 80, includes a smooth uppersurface and a smooth lower surface indicated, respectively, by referencenumerals 92 and 94, and an intermediate portion 96 between the twosmooth portions. The intermediate portion 96 has a plurality of circularapertures 98 extending through. The size of the apertures 98 and theirparticular orientation, may vary, again as desired to provide a desiredshock absorbing and rotational or torsional characteristics of theelement 90.

[0038]FIG. 7 discloses a double element 100 which includes an outerelement 102 and an inner element 104. The elements 102 and 104 aredifferent in thickness and may be different in composition to providethe desired shock absorber and twisting or torsional characteristics ofthe element 100.

[0039] The elements 40, 70, 80, 90, and 100 are essentially sleeveswhich connect the pyramid adaptor 12 to the pylon 30. Their particulardesign characteristics, as illustrated in the drawing figures, and whichmay be of other different configurations, are designed to providespecific shock absorber and torsional characteristics for a particularapparatus, or a particular user, or the user's desired activities. Thesecharacteristics, obviously, may vary depending on the size of the personto whom the apparatus 10 will be secured, to a particular situation, andthe like.

[0040] For example, if the apparatus 10 is to be used for merelywalking, one particular sleeve element 40 may be used, while a differenttype of sleeve or element may be used if the apparatus 10 is to be usedfor running, playing golf, or some other activity. Indeed, an individualmay have several sleeves or elements which may be interchanged with thesame pyramid adaptor and pylon, depending on the desired activities ofthe user. Also, as discussed above, the use of a third clamp, disposedbetween the two clamps which secure the elastomeric sleeve element tothe respective pyramid adapter and the pylon, may also be used to varythe characteristics of any particular sleeve element by varying thelocation of the third clamp on the sleeve and the pylon.

[0041]FIG. 8 is a front view of a sleeve 120, which comprises anotheralternate embodiment of an elastomeric element of the apparatus of thepresent invention. FIG. 9 is a top view of the apparatus 120, takengenerally along line 9-9 of FIG. 8. For the following discussion,reference will be made to FIGS. 8 and 9.

[0042] The sleeve 120 is an elastomeric element having a generallycylindrical configuration, like the other elastomeric elements discussedabove. The sleeve 120 comprises an elastomeric cylinder 122 which has aninner bore 124. The bore 124 receives the mating portions of the clampland 18 and the pylon 30, as may be understood from FIG. 3. The cylinder122 includes a top surface 128 adjacent to a top clamp portion 126. Atthe lower portion of the cylinder 122 is a bottom clamp portion 130. Thebottom clamp portion 130 is adjacent to a bottom surface 132.

[0043] Extending between the top and bottom clamp portions 126 and 130are a plurality of vertically axially extending grooves 134. Between thegrooves are a plurality of axially extending ribs or lands 136. Thegrooves 134 are generally aligned with the top and bottom clamp portions126 and 130. That is, the outer diameter of the cylinder 122 at theclamp portions 126 and 130 is generally the same as the diameter of thecylinder 122 at the grooves 134. Accordingly, the diameter of thecylinder 122 through the ribs or lands 136 is greater than the diameterof the cylinder 122 at the clamp portions and at the grooves. This isbest shown in FIG. 9.

[0044] The purpose of providing the greater diameter of the cylinderthrough the ribs or lands 136, with adjacent grooves 134, is to providea stiffening of the elastomeric element to provide more vertical oraxial shock resistance without sacrificing any torsional or rotationalcapability, as compared to the previously discussed embodiments. Thevertical ribs 136 and the grooves 134 provide such capability.

[0045] The different embodiments provide specialized shock absorbing andtorsional movement characteristics for different purposes. As discussedabove, the apparatus 120 provides somewhat greater vertical shockabsorbing characteristics while minimizing additional rotationalresistance, as compared to the previously discussed embodiments. Thenumber of lands and grooves, and the extent or increased diameter of thelands, as compared to the diameter of the groove portion of theapparatus, may vary according to the size or weight of the user of theapparatus and according to the specific use which the user may desire.Specific elements or apparatus for an individual may vary depending uponthe specific use or purpose desired by the user. Thus, a user may desireone size for ordinary walking and others for athletic uses, and thelike.

[0046] Moreover, the composition of the elastomeric material out ofwhich the sleeves are made may vary according to the same generalparameters as discussed in the next previous paragraph, namely the sizeof the user and the purpose of the sleeve. Thus, for any individualuser, elastomeric sleeves may vary in configuration and composition.Since the sleeves are easily and quickly changed, a user may have anumber of sleeves, each with different characteristics to be useddifferent purposes or different specific uses.

[0047] While the principles of the invention have been made clear inillustrative embodiments, there will be immediately obvious to thoseskilled in the art many modifications of structure, arrangement,proportions, the elements, materials, and components used in thepractice of the invention, and otherwise, which are particularly adaptedto specific environments and operative requirements without departingfrom those principles. The appended claims are intended to cover andembrace any and all such modifications, within the limits only of thetrue spirit and scope of the invention.

What we claim is:
 1. Prosthetic shock absorber apparatus comprising incombination: a cylindrical element; a pylon movable relative to thecylindrical element; an elastomeric element, having a plurality ofvertically extending grooves, disposed about the cylindrical element andthe pylon; a first clamp for securing the elastomeric element to thecylindrical element; and a second clamp for securing the elastomericelement to the pylon, whereby the elastomeric element absorbs axialshocks and permit torsional relative rotation as the pylon and thecylindrical element move relative to each other.
 2. The apparatus ofclaim 1 which further includes a top clamp portion on the elastomericelement, and the first clamp is disposed on the elastomeric element atthe top clamp portion.
 3. The apparatus of claim 2 which furtherincludes a bottom clamp portion on the elastomeric element, and thesecond clamp is disposed on the elastomeric element at the bottom clampportion.
 4. The apparatus of claim 3 which includes a plurality ofvertically extending lands between the plurality of vertically extendinggrooves.
 5. The apparatus of claim 4 in which the plurality of groovesare aligned with the top and bottom clamp portions.